Which of the following would increase the expected current value of a stock valued using the dividend valuation model?

Question $29$ options:

$1)$

An increase in the expected dividend growth rate

$2)$

A decrease in the expected dividend growth rate

$3)$

A decrease in the required rate of return

$4)$

Answers a$.$ and c$.$ are both correct

$5)$

Answers b$.$ and c$.$ are both correct