Here are the answers to your questions:

**Question 50:** You'd better **A. spend** too much money on shopping or you won’t have any left.

**Question 51:** He hoped **A. winning** the music competition and got a chance to record his debut album.

**Question 52:** Climate change is a serious **A. environmental** issue that requires both action from governments and individuals worldwide. (Note: The correct form is "environmental," which was mistakenly listed in the options as "environment" twice; it should include "environmental").

So the correct answer for Question 52 based on your initial choices would be **A. environment** since that is the only viable option, even though "environmental" would be more accurate.