Two capacitors, C1 and C2, are connected in series across a source of potential difference. With the potential source still connected, a dielectric is now inserted between the plates of capacitor C1. What happens to the charge on capacitor C2?

Answer
a. The charge on C2 increases.
b. The charge on C2 remains the same.
c. The charge on C2 decreases.

a. The charge on C2 increases.

Explanation:

We know that voltage is divided in inverse ratio in series combination of capacitor as,

V = Q/C

The dielectric slab between the plates of C2, its capacitance will be increased as C = k£°/d

So, on inserting dielectric slab between the plates of C2, the potential difference across C2, decreases and the potential difference across C1, will now increases.

the entire statement is true and correct.  

there's no diagram, nothing is illustrated, and no question is asked.

connect the batteries in series and hope