Final answer:
The correct answer for the communication equipment used in normal confined space operations is both rope signals and hard wire systems, making option d ('b' and 'c') the correct choice.
Step-by-step explanation:
In normal confined space operations, communications equipment can consist of rope signals or can consist of hard wire systems. Therefore, the correct answer to the question is d. both 'b' and 'c'. It is critical for safety in confined space operations to have reliable communication systems in place. Rope signals are a simple but effective means for workers to communicate without the use of technology, while hard wire systems provide a dependable, direct communication link that can be crucial in emergency situations or when verbal communication is not possible due to the environment.