Chemistry · Classification of Elements and Periodicity in Properties

Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): Mendeleev left certain gaps under aluminum and silicon in his periodic table. Reason (R): Mendeleev predicted the existence of gallium and germanium before their discovery and described some of their general physical properties. In the light of the above statements, choose the correct answer from the options given below:

1. Both (A) and (R) are true and (R) is the correct explanation of (A).
2. Both (A) and (R) are true but (R) is NOT the correct explanation of (A).
3. (A) is true but (R) is false.
4. (A) is false but (R) is true.