Stock Q has a beta of $0\mathrm{.}55$ and Stock T has a beta of $1\mathrm{.}20.$ Which of the following statements must be true about these securities$?($Assume the market is in equilibrium.$)$

a$.$ Stock Q would always be a more desirable addition to a portfolio than Stock T$.$

b$.$ The required return on Stock Q and Stock T will be the same.

c$.$ When held in isolation, Stock T has more risk than Stock Q$.$

d$.$ Stock T would always be a more desirable addition to a portfolio than Stock Q$.$

e$.$ The required return on Stock T will be greater than that on Stock Q$.$