Responding to the public’s fascination with―and sometimes undue alarm over―possible threats from asteroids,
a scale developed by astronomers rates the likelihood that a particular asteroid or comet may collide with Earth.
Option Elimination -
(A) a scale developed by astronomers rates the likelihood that a particular asteroid or comet may - we need a noun for the ING modifier that can logically refer to who responded.
(B) a scale that astronomers have developed rates how likely it is for a particular asteroid or comet to - same as A.
(C) astronomers have developed a scale to rate how likely a particular asteroid or comet will be to - deception here is "to rate," which is correct, and so is "for rating." "how" is introduced as a relative clause, a noun modifier. Ok, let's get our hands dirty here.
- "Rate how likely" is redundant. Ok, let me give an example. How about if we say, "He gave a gift as a present." here, "gift" and "present" convey the same meaning. Likewise, "rate" and "how likely" mean the same. They encapsulate the notion of quantifying the chance or possibility of an event occurring on a scale or in numerical terms.
- "Will be to" is not grammatically incorrect, but it adds complexity. E.g., "She will be going to travel." The phrase "will be going to" is redundant and overly complex. In the sentence, "will be to" doesn't contribute significantly to the meaning and makes the expression convoluted.
Let's unpeel it.
The act of determination of future events is happening now and not in the future. Don't confuse the "act of determination" with "the event." The act is happening now (so will is wrong); the event itself about which we predict the likelihood is happening in the future, so the future for that is perfect. Or we can see that the scale is being used "presently" to assess the probability of a future event (asteroids colliding with Earth).
Revised version: "How likely a particular asteroid or comet is to collide with Earth." Changing "will be" to "is" makes the sentence more immediate and concise. "Is" implies the collision's current probability or likelihood rather than it (it refers to probability or likelihood) as a future event. This immediate expression makes the sentence more clear.
For instance, imagine explaining the weather forecast:
"How likely it will be to rain tomorrow" suggests a future event.
"How likely it is to rain tomorrow" presents the current probability of rain.
(D) astronomers have developed a scale for rating the likelihood that a particular asteroid or comet will - Let's unpack it. Add it to your brain trust "for rating" is ok. Don't even reject based on idiom. There are thousands of idioms, so whether you are native or non-native, there is a high probability that you may experience googly
. So now, let's talk about the elephant in the room.
- "Rating the likelihood" is correct. Let me explain mathematically to make more sense for you. Imagine statisticians develop a scale to rate the likelihood of rolling a six on a fair six-sided die. Let's take "rate the likelihood." Imagine two scenarios
a. If the statisticians "rate" the likelihood of rolling a six as nine on a scale of 1 to 10, it suggests a higher probability of rolling a 6.
b. If the statisticians "rate" the likelihood of rolling a six as two on a scale of 1 to 10, it suggests a lower probability of rolling a 6.
They developed the scale "to rate" or "for rating" the likelihood on a scale of 1 to 10. The "relative clause," which modifies nouns, modifies likelihood. The relative clause beautifully encapsulates the future event using "will."
(E) astronomers have developed a scale that rates the likelihood of a particular asteroid or comet that may - here, the critical issue is a prepositional phrase " of a particular asteroid." Likelihood of an asteroid. Seriously? Not correct.
I hope it helps.