If I am understanding this question correctly, you're looking for the answer choice that (most closely) reflects true circumstances faced by the U.S. which were not supportive of the American cause in WWI. This is why I would select (C). Lack of Naval Capabilities.
Of course, the U.S. did not lack (completely, anyway), a navy; however, its naval capabilities (compared to both enemy/Germany and ally/Britain) were not as effective. How do we know this? If we look at the early years of WWI (during the U.S.'s neutrality period), the British-imposed blockade on German-bound merchant ships (including American ones) was answered by Germany's strategic use of submarines (U-boats) and their announced intention to sink any ship suspected of transporting military supplies. Germany's promise played out in the 1915 sinking of the passenger ship Lusitania (killing 1198, including 128 Americans) - an action which generated significant anti-German publicity in the U.S.
Answer Choice (A). Lack of Military Preparedness is not correct, since Wilson enacted precisely this state after his 1916 reelection; (B). Lack of Enthusiasm by American Public is not the answer, as per the Lusitania incident (described above) as well as the Zimmerman Telegram (early 1917); and (C). Lack of Industrial Strength is not correct, since the U.S. was firmly established as an international industrial power by the early twentieth century.
I hope this helps - good luck!