Question

Read the statement carefully
$X:$ the resistivity of a semiconductor can be decreased by adding suitable impurity to it
$Y:$ introduction of impurity to semiconductor creates excess charge carriers of one type
$Z$ : introduction of small quantity of the order 1 part per $10^{6}$, controls the conductivity in the predictable manner
Select the correct statement(s) from the following:

• A. both $X$ and $Y$ are true and $Z$ is false
• B. both $X$ and $Y$ are true and $Z$ is the correct reason for $X$
• C. both $X$ and $Y$ are true and $Y$ is the correct reason for $X$
• D. $X, Y$ and $Z$ are true and $Z$ is the correct reason for $X$.

Answer 1

Answer: (C)

Correct answer is (c) both $X$ and $Y$ are true and $Y$ is the correct reason for $X$