What does the word "murky" （Para. 3) probably mean？A．Unclear.B．Significant.C．Obvious.D．Exa

What does the word "murky" (Para. 3) probably mean？

A．Unclear.

B．Significant.

C．Obvious.

D．Exaggerated.

请帮忙给出正确答案和分析，谢谢！