hello, i am struggling to understand the answer, please explain!

Q11. ConsidertheAD-AS diagram below: In the standard closed-economy ta se we have considered so far, which of the following might explain Y- the change from point a iso point b? 2' 53 F' F' A] B} D] I} K} 1-} A dea'ease in population. A decrease in technology level. A decrease in consumer and busine; condence. A decrease in capilal depreciation rate. i. is plausible, i. is plausible, i. is plausible, i. is plausible, i. is plausible, i. is plausible, i. is plausible, i. is plausible, i. is not plausible, i. is not plausible, i. is not plausible, i. is not plausible, M} i. is not plausible, N] 0] P] Answer: N i. is not plausible, i. is not plausible, i. is not plausible, ii. is plausible, ii. is plausible, ii. is plausible, ii. is plausible, ii. is not plausible, ii. is not plausible, ii. is not plausible, ii. is not plausible, ii. is plausible, ii. is plausible, ii. is plausible, ii. is plausible, ii. is not plausible, ii. is not plausible, ii. is not plausible, ii. is not plausible, iii. is not plausible, iii. is not plausible, iii. is not plausible, iii. is not plausible, iii. is not plausible, iii. is not plausible, iii. is plausible, iii. is plausible, iii. is not plausible, iii. is not plausible, Source: This question comes from the chapter 4 material. iv. is plausible iv. is not plausible iv. is plausible iv. is not plausible iv. is plausible iv. is not plausible iv. is plausible iv. is not plausible iv. is plausible iv. is not plausible iv. is plausible iv. is not plausible iv. is plausible iv. is not plausible iv. is plausible iv. is not plausible Explanation: The diagram shows a decrease inAD. Options i and ii are not plausible as decreases in both population level and technology level will decrease Y\