Two Infectious Disease Epidemiologists Want to Investigate a New Laboratory

Two infectious disease epidemiologists want to investigate a new laboratory test that identifies TB infections.Dr.Merritt uses the standard test,which has a sensitivity of 80% and a specificity of 90%.Dr.Foundry uses the new laboratory test,which is 90% sensitive and 99% specific.Now,epidemiologists decide to run those two test as sequential tests (two-stage testing) .What is the effect on net sensitivity of sequential tests?

A) 72%
B) 80%
C) 89%
D) 90%
E) 98%