I often use sentences such as "the challenges of doing...", "the challenges xx have to face" for my research. I'm trying to translate that into Japanese, but I have trouble finding a word for "challenge". 課題 and 問題 have been suggested to me, but neither seems to fit perfectly. 課題 is probably more appropriate, but the meaning of "challenge" doesn't seem to be the main one.
新規有機農家の課題は何ですか？ What are the challenges for new organic farmers?
有機農業を始める課題は。。。 The challenges of starting organic farming are...
Would these be okay in my case? Is there any better option?