What Was the Main Difference Between the Asch Line-Matching Studies

What was the main difference between the Asch line-matching studies and the Sherif autokinetic effect study

A) The Asch study included random assignment of participants whereas the Sherif study did not.
B) In the Asch study there was a correct answer whereas in the Sherif study the answer was ambiguous.
C) The Asch study focused on the participant's attitudes whereas the Sherif study focused on the participant's motivations.
D) The Asch study focused on informational conformity whereas the Sherif study focused on normative conformity.