Having logged thousands of hours watching primates from chimpanzees to

Having logged thousands of hours watching primates from chimpanzees to macaques, chimps and other primates are no longer thought to be natural-born killers by Dr. Swenson, they are attuned to peacemaking.

Having logged.................from chimpanzees to macaques is modifying noun 'Dr. Swenson'. That cuts off option A,D and E. The sentence somehow means chips looikng at other primates and also, 'they' at the end of last comma is ambiguous and creates irrelevant meanings.

A. chimps and other primates are no longer thought to be natural-born killers by Dr. Swenson, they

B. Dr. Swenson has come to believe that far from being natural-born killers, chimps and other primates
CORRECT. The sentence uses correct tense because an event started before and is continuing. Look at the phrase "Having logged.................from chimpanzees to macaques"-a past event continuing till now. So, 'has come' is the correct tense. Also, 'being' usage is correct which indicates a event is happening now.

C. Dr. Swenson has now the belief that far from being natural-born killers, chimps and other primates
INCORRECT. An event is continuing and 'has now the' is not the correct tense one could use.

D. chimps and other primates are not longer thought to be natural-born killers by Dr. Swenson, they
E. chimps and other primates are no more thought to be natural-born killers by Dr. Swenson, they

Having logged thousands of hours watching primates from chimpanzees to macaques, chimps and other primates are no longer thought to be natural-born killers by Dr. Swenson, they are attuned to peacemaking.

Simply going by the meaning of the sentence someone watched primates, logging thousands of hours, only B and C make the cut as ‘chimps and other primates’ can’t do that otherwise it would be illogical. So, in ‘C’ Dr. Swenson has some belief as if it’s not his own i.e. the option changes the meaning slightly which is not the case. Option ‘B’ on the other hand clearly communicates that Dr. Swenson watched primates for hours and finally concluded that they are not natural born predators instead primates are peace-loving animals.

A. chimps and other primates are no longer thought to be natural-born killers by Dr. Swenson, they – WRONG.
B. Dr. Swenson has come to believe that far from being natural-born killers, chimps and other primates – CORRECT. As discussed above.
C. Dr. Swenson has now the belief that far from being natural-born killers, chimps and other primates – WRONG.
D. chimps and other primates are not longer thought to be natural-born killers by Dr. Swenson, they – WRONG.
E. chimps and other primates are no more thought to be natural-born killers by Dr. Swenson, they – WRONG.

Answer (B).

A,D,E can be eliminated as Having logged thousands of hours watching primates from chimpanzees to macaques modifies chimps and primates.
Between B and C
Dr. Swenson doesn't come to a BELIEF(To have faith/noun) , he just started believing(verb/started accepting the truth) that primates and chimps are attuned to peacemaking based on long hours of watching them.
So B wins..

#1. Modifier

Does "having logged thousands of hours watching primates from chimpanzees to macaques" modifies chimps and other primates or Dr. Swensen. -> Definitely Dr. Swensen because otherwise it would not make sense
- So Eliminate A,D and E

ฺBetween B and C
B. Dr. Swenson has come to believe that far from being natural-born killers, chimps and other primates - more concise
C. Dr. Swenson has now the belief that far from being natural-born killers, chimps and other primates

Therefore, B is the answer choice

The opening modifier demands subject as the doer of the action (the one who has clocked thousands of hours).

Eliminate A,D and E.

Between B and C, the differences are minute.

B says that he say come to believe something after doing something else

C says that he has a belief after doing something.

B is preferred as it shows that the subject didn't hqve the belief in the beginning and now he has come to believe.

B is the answer

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MEANING
who has logged hours watching primates? dr.S
who is far from being natural-born killers? chimps and other primates

(C) "has now the belief" imps she now possess the belief, which is unintended and distorts the meaning;
the intent is that she has now "realized" something;

Answer (B)

Official Explanation

Correct Answer: B

The best answer is B. The noun that comes directly after the comma is modified by having logged thousands of hours watching primates from chimpanzees to macaques. Answers A, D, and E illogically have the chimps observing other primates.

B. First part of the sentence should modify the subject. Subject is Dr. Swenson.

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