This is a test of commonsense with single/multi-choices. Complete the next sentence:

How to throw a faster fastball
Perfect your grip.
There are two primary grips for the fastball: the four-seam and the two-seam. The four-seam generally gathers more velocity but some pitchers find the two-seam more comfortable and easier to command.

A). A seam at the center of the hand is often the most awkward part of the fastball. For the same reason: the seam of a fastball is made up of seven beads in and a single bead..
B). Many experienced pitchers will switch between the two options when they want to emphasize velocity or movement respectively but you should stick with one until you're fully comfortable with it. For the four-seam grip, place your index and middle fingers across the seams where they form a horse-shoe shape with a comfortable amount of space between them..
C). Beyond holding the ball, you should use both hands to closely access the grip. If you are an experienced pitcher, simply hold the ball with both hands and slap the ball on the edge of your glove..
D). This flexibility will put more experience on the pitch, but might result in more accurate throws. That is true even for pitchers who only have as small hands as two, who hold the ball between them while they throw..
The answer is:
B).