"The rejection of tradition" is the modernist theme highlighted in the extract (Option A). See the list below for further information on modernist themes.
<h3>What is the definition of a Modernist Theme?</h3>
The concept of divergence from established norms is identified as a modernist subject in literature.
Decipherability means to determine the meaning of. And as it has suffixed to 'able', i.e. Decipherable, it means the one which could be determined like that