The World War II design that could transform World War I

Which British World War II warship design would be most useful if taken back to World War I?

The choices include LCM(1) landing craft for amphibious operations and Bay-class frigates for convoy protection that could be expanded through merchant-yard construction.

The transferable design must be something World War I industry could build and employ. Vanguard has the advantage of main guns already familiar to the Royal Navy, while escorts and submarines offer other ways to change the war. Clarke chooses the LCM(1), whose petrol machinery is described as an evolution of engines already available. Faster landings could change the prospects at Gallipoli, provided the craft arrive with troops and a doctrine coordinating their approach with naval gunfire. Some craft could also be adapted for minesweeping. The alternatives include Bay-class escorts built in commercial yards and T-class submarines attacking the High Seas Fleet as it leaves port.