<span>C. They also think whale-hunting is immoral, because the methods used yo kill whales are cruel and inflict intense suffering on the animals.</span>
B. Make every word count - use only important words.
This is true because when you have as few as 750 words to state your point, you need to pack as much detail and facts as you can into a tiny amount of space. Chances are, they've provided either a prompt or several questions for you to answer, and you need to answer all of them or the entire prompt will a lot of description and you need to support whatever you said with detail and/or facts.
The function of the infinitive phrase in the sentence <em>To win a marathon is my goal </em>is object of the verb.
It is definitely an object, and it would follow a verb if it were a normal ordering of words in the sentence (My goal is to win a marathon), and since it is not preceded by a preposition, it cannot be object of the preposition, but of a verb.
