If colour is spreading too quickly and uncontrollably on a wet surface, what should be corrected first?

Correct answer: Reduce excess surface moisture

The governing concept is moisture control in wet-on-wet watercolour. A puddled or excessively wet surface lets pigment travel rapidly beyond the intended mark, so the first correction is to remove or reduce excess surface water while keeping the paper suitably damp. Option A is correct. Adding water, wetting the paper further, or rubbing forcefully increases disturbance and makes the spread less controllable.