The correct answer is B. from.
The word “refrain” means “to stop oneself from doing something”. In this sentence, the speaker is saying that the woman could not stop herself from crying. The preposition “from” is used to indicate that the woman was trying to stop herself from crying, but was unsuccessful.
The other options are incorrect because they do not make sense in the context of the sentence. The word “to” is used to indicate a purpose or goal. The word “by” is used to indicate a means or method. The word “with” is used to indicate a tool or instrument.
Here are some examples of how the other options could be used in a sentence:
- She decided to refrain from eating chocolate.
- She refrained from eating chocolate by putting it out of sight.
- She refrained from eating chocolate with a lot of willpower.