Question

1. using the figure above, choose the true statement:

a. points a, b, and c are collinear.

b. points a, b, and c are coplanar.

c. point f lies on line de.

d. point c lies on plane def

Explanation:

• Option A: Collinear points lie on the same line. A, B, C don't share a line (A and B are on a horizontal line, C is off that line), so A is false.
• Option B: Coplanar points lie on the same plane. A, B, C are on the lower blue plane, so they are coplanar.
• Option C: Line DE and point F: DE and F are on different lines in plane DEF (DE and DF are different lines), so F is not on DE, C is false.
• Option D: Plane DEF is the upper blue plane, and C is on the lower plane, so D is false.

Answer:

B. Points A, B, and C are coplanar.