Both answers are accepted :"The women sold the yellow shoes." and "Women were selling yellow shoes.". The meaning is very different. Explanation anyone?
Russian doesn't have specific tenses like English has – the sentence simply uses a verb in past tense, and the difference you wrote about need to be implied from context. Since it isn't provided, both answers are accepted.
"The women sold..." is not correct. The exercise says "Женщины..." meaning more than one