Li Mei is writing a progress report on the development of a new inventory system for a client. She and her team faced a technical glitch last week, which has since been solved. What is the best way to present this information to the client?

$"$We overcame a major technical glitch last week. We are now on track to finish the work by the due date."

$"$I$\text{'}$m really sorry, but we're running two days behind schedule. We will however be back on schedule by the end of the month."

"Please accept our sincere apologies. We will be unable to complete the work according to the estimated deadline."

"Owing to the huge technical problem we faced last week, we are a little behind schedule. We may need an extension on the deadline"

$"$We have had a major problem last week because of which our work is affected to an extent. However, we should be able to finish by the due date."