Arrange in hierarchical order by date the following inventions:

I. – Census machine; Il. – Abacus; lll. – Slide rule; IV.- Difference engine.

A. I, lI, IlI and IV
B. I, Il, III and IV
C. I, II, IV and llI
D. I, IV, IlI and l

Correct Answer:

Option A – I, lI, IlI and IV