Final answer:
The LLP on a heat pump is physically tapped near the outdoor coils, which function as the evaporator in heating mode, therefore, the answer is b) Indoor coil.
Step-by-step explanation:
The LLP (Low Pressure Port) is typically used to measure the suction line pressure of refrigerants in heat pump systems. In the context of a simple heat pump with its four basic components - the condenser, expansion valve, evaporator, and compressor - the LLP would be physically tapped closest to the part of the system where the refrigerant is at its lowest pressure after the heat exchange process, but before it gets compressed again. Based on the provided descriptions and the function of each component, the LLP is typically located near the outdoor coils, which function as the evaporator in heating mode. Thus, the correct answer to the question 'Where is the LLP physically tapped into the system on this heat pump?' would be option b) Indoor coil.