To get to the bottom of something would mean that their is something mysterious going on, and that person wants to know everything about it as soon as possible. Its like saying that you would like to 'crack a code', or solve the case.
Answer:
C. I think Carine will bring her mother’s falafel to International Night because her friends are willing to try new foods.
In some cases like the word vice, the negative connotation stems from a direct definition of the word(vice means wicked, but another definition is 'a substitute for' so 'vice president'). In other cases, word may be used in a culture to identify a group or individual that is portrayed negatively, thus modifying the inherent definition of the word to better portray how society thinks of the word.
In the sentence given, it is a gerund and not an infinitive phrase. The complete gerund phrase in the sentence is "jumping rope". The gerund is the word "jumping". A gerund is a word that takes the -ing form of the verb, but functions as a noun. This gerund phrase is used as the subject of the sentence.