According to the Citrix documentation, the -denySSLReneg parameter specifies the type of SSL renegotiation that the Citrix ADC denies. The possible options are:

NONSECURE: Deny renegotiation requests from a client if the initial handshake between the Citrix ADC and the client is not secure. A secure handshake is one in which both parties prove their identities to each other by presenting valid certificates.

FRONTEND_CLIENT: Deny renegotiation requests from a client on a front-end SSL connection, regardless of whether the initial handshake is secure or not. A front-end SSL connection is one in which the Citrix ADC communicates with the client over SSL.

ALL: Deny all renegotiation requests from a client on a front-end SSL connection and from a server on a back-end SSL connection. A back-end SSL connection is one in which the Citrix ADC communicates with the server over SSL.

NO: Allow all renegotiation requests.

Therefore, the correct answer is A and C.