Options:
A.
B.
C.
D.
Sign in to view the correct answer and detailed explanation.
Study with fewer interruptions on Android
Use Ulearngo on a verified device for smoother past-question study.
Ulearngo is an independent study app. It is not affiliated with, endorsed by, or representing Obafemi Awolowo University (OAU). Always confirm official exam, admission, registration, syllabus, timetable, and result information from OAU admissions.
Earlier discussion
1 older comment kept for context.
Victor
Sand produces friction thereby increasing the surface tension. On like option 1,2 and 3 which reduces friction