Animal intelligence is a hotly debated topic in the biological science

So first I summarized what the reading is about :
1. animal intelligence & raven was mentioned as example.
2. observations of raven behaviors.

Here are my answers :

1. The author is primarily concerned with
A. demonstrating how animals learn behaviors in a controlled environment
This seems tempting since there is a lot of recycled language, however the passage is about the behaviors of animals that show their intelligence, not about how animals learn new behaviors.
B. refuting claims that observations of raven behaviors demonstrate cognition
The passage did not refute anything.
C. discussing tool use in different bird species
Briefly mentioned in para 1, but this answer is quite ambiguous also.
D. providing examples of raven behaviors that may demonstrate intelligence
This is the correct answer, the first para mention raven and the 2nd para explains this.
E. questioning the importance of fieldwork in the biological sciences
The author didn't question anything.

2. The author of the passage would be most likely to agree with which of the following statements?
A. The feeding behavior of ravens can best be explained as a stimulus-response mechanism.
In the passage : "he did not consider to be examples of a simple, stimulus-response mechanism."
B. Observations of ravens in their natural environment raise interesting questions about their intelligence.
I crossed out the other 4 answers then came back to B.
C. While caution should be used when interpreting field observations, raven behavior suggests that these birds do not demonstrate cognition.
The whole passage is about raven possess to some extent animal cognition and this answer refutes all, so cross this out.
D. Ravens are the only corvids to be observed undertaking activities that suggest the capacity to solve problems.
The "only" here is too strong to be inferred from the passage.
E. Biologists are firmly convinced of the lack of intelligent activity in the animal kingdom.
Definitely wrong.

3. The author cites examples of the use of tools by crows and jays to provide support for which of the following claims?
We can identify this piece of information in passage 1, so anything related to para 2 will be false, so cross out C & D. Answer A is against the whole idea of para 1, so cross out. Answer E uses "never" which is too strong to be inferred from any sentence in the passage, so cross out. This leaves me with B.

4. Which of the following statements about the evidence of intelligence in raven behavior is best supported by the information presented in the passage?
A. Raven intelligence is no longer a subject of debate.
No source.
B. Raven feeding behavior provides evidence of intelligence on par with human beings.
Nowhere did the passage compared raven with human beings.
C. Field observations are important in the field of animal cognition.
Not mentioned in the passage but after cross out other 4 answers, this seems to be an appropriate answer, seems the author used the whole 2nd para to describe the results of hundreds of hours of field observations of biologist Bernd Heinrich.
D. Tool use by birds is an unambiguous example of intelligent behavior.
In para 1 : "While scientists disagree about whether or not the use of tools is an unambiguous example of animal intelligence", so this sentence is not confirmed, cross it out.
E. Ravens only call each other to a kill site when food resources are plentiful.
In para 2 : "alerting other ravens to carcasses benefits each individual in times of scarcity.", cross this out.