Which of the following is an allowable substitution for CATVP type cable?

The correct choice, BLP (Buffered Low Power) cable, serves as an allowable substitution for CATVP type cable because it meets the necessary requirements for surveillance and security systems that CATVP cables are typically used for. These cables are designed for low voltage applications and have attributes that ensure effective data transmission over short distances, similar to the CATVP specifications.

BLP cables are often employed in wiring that supports video, audio, and data signals without interference, which aligns with the primary functions of CATVP type cable. The specific design characteristics and shielding of BLP cables make them suitable for the same applications, ensuring that performance remains consistent even when substituting for CATVP.

The other choices do not satisfy the conditions needed for an appropriate substitute. Their specific construction and intended uses do not align as closely with the functionalities inherent in CATVP type cabling. Thus, BLP stands out as the best alternative.