Answer: (d) I like trying new activities; therefore, I'm looking forward to learning to snowboard.
Step-by-step explanation: a conjunctions is a word that joins or connects sentences or phrases, the word "therefore" is an adverb that acts like a conjunction (a conjunctive adverb). When we use words like "therefore", "however", "moreover" etc, to connect to independent clauses, we need to put a semicolon before those words, and a comma after: "I like trying new activities; therefore, I'm looking forward to learning to snowboard.