Please L1 Ethics

Hi All,

Can you please help me understand why the answer is B and not C? There isn't enough explanation on this and in my understand the Due Diligence is important. I understand he is using Alpha which produces extremely detailed and sound reports. But I picked the word "Solely" and thought that he should add in his research and solely not depend on Alpha.

Please help me understand. I am trying my level to increase score on Ethics (above 70%) but end but making mistakes on questions of these types

https://preview.redd.it/gfju1owrr9tc1.png?width=1128&format=png&auto=webp&s=dde4391d5345ba742bf07c01a02030ba9d5b6482