What is the MOST LIKELY reason that Londoners no longer rely on the Thames as their main mode of transportation?

Question

Responses
A Modern forms of transportation are more convenient.Modern forms of transportation are more convenient.
B The river is too polluted for people to travel across.The river is too polluted for people to travel across.
C Military personnel have blocked off parts of the river.Military personnel have blocked off parts of the river.
D Unpredictable floods make traveling the Thames dangerous.

Answer 1

A Modern forms of transportation are more convenient.