I would say a) joy but i’m not a 100% sure
Answer:
opportunity costs are the alternative choice in which you could make when making a financial decision while a trade-off is something that you could switch out in order to make a different decision
It helps you and develops your skills.
An inference is a conclusion that a reader draws based on evidence in a text.
B. This is answer is mentioning multiple parts which are dependent on the sentences structure.