Tech a states that automobiles became more affordable later due to henry ford bringing in the concept of the assembly line. tech b states that the automobiles became the predominant mode of transport due to introduction of smaller gasoline engines. who is correct?

Tech A is correct

Explanation:

When the assembly line was introduced into the production process, the costs of car's production was dramatically reduced. The laborers cost is lower and the time for the process is shorter. The introduction of Ford's T model became in the revolution of production, due to the different costs reduction the cars prices became affordable for the people and the car started to he more and more popular. With the time, more companies introduced this production method and all the market started to be more competitive.

With the time the companies have started to create more efficient engines, however, the cars have been the most important mean of transport more for more than 50 years.