Read the sentences. the inventor initially struggled to solve the problem. she discovered an ingenious solution. which revision uses a coordinating conjunction to combine the sentences? the inventor initially struggled to solve the problem until she discovered an ingenious solution. the inventor initially struggled to solve the problem; however, she discovered an ingenious solution. the inventor initially struggled to solve the problem, but she discovered an ingenious solution. the inventor initially struggled to solve the problem before she discovered an ingenious solution.