Two Projectiles Are Launched 50 $\degree$ Above Horizontal but with Different Initial Speeds

Multiple Choice

Two projectiles are launched 50 $\degree$ above horizontal but with different initial speeds. Which of the following must be true while the projectiles are in the air? (Ignore air resistance.)

A) The projectiles will reach the same maximum height.
B) The horizontal speeds of both projectiles are the same.
C) The horizontal accelerations of both projectiles are the same: zero.
D) The one with larger initial speed will experience a larger vertical acceleration.