Premise: No player who strikes out more than half of his runs at-bat often is truly a great baseball player.

Conclusion: Only truly great players deserve to be chosen for the Little League All-Star team, so none of the Mudskippers players deserve to be selected as All-Stars this year.

Let's find the option that is most fit to strengthen this argument.

Option A - Incorrect:
This answer choice is too general in rating all Mudskippers players are terrible baseball players. The fact, that they don't deserve to be chosen for the Little League All-Star team this year does not mean that are terrible.

Option B - Incorrect:
This is wrong and irrelevant to the information portrayed in the passage.

Option C - Incorrect:
This answer choice contradicts the passage conclusion that says "none of the Mudskippers players deserve to be selected as All-Stars this year." So, therefore, it doesn't strengthen this argument.

Option D - Correct:
This claim strongly supports Washington Mudskippers Team's aim of presenting Jason as their top-rated shortstop as portrayed in the passage. Thus, this answer choice strengthens the argument the most.

Option E - Incorrect:
This answer choice doesn't provide much direct relevant information to the passage. We know from the passage that "none of the Mudskippers players deserve to be selected as All-Stars this year," but we are not sure if Mudskippers players will be even considered not to talk of them deciding if they will play or not.