Class of admission ; the kind of visa you used for the last entry - such as B1/2, H-1B or L-1A/B, etc.
Reason: to take care of family matters.
Any application can be rejected for reasons. But approval percentage is much higher than rejection, especially I-131. CIS will not reject directly, they always send you RFE to give you a chance to explain, to submit more documents as they request.