Final answer:
Without audio, it's impossible to be certain, but if a piece includes only women's voices and piano, the answer is that it's performed with voices and a piano. It's essential to consider historical biases in classical music and what is presented as 'worthy' music, which traditionally focuses on works by white, deceased male European composers.
Step-by-step explanation:
Without hearing the piece in question, it's not possible to determine with certainty which option is correct about what you're hearing. However, it's relevant to note that throughout history, the field of classical music has often highlighted works created by white, mainly deceased, male composers from Europe. It is often these compositions that are considered most worthy of study and performance. When it comes to choral works, if a conductor presents a piece, it usually reflects this historically revered demographic. If the piece you are hearing features a single gender (only women's voices) and includes instrumentation (such as a piano), then the correct answer would likely be that this is performed with voices and a piano. Response b, suggesting that the piece is polyphonic and acapella, means it has multiple independent melodies sung without instrumental accompaniment, which contravenes the inclusion of piano. Options a and d may be correct depending on the specifics of the piece but are less informed guesses without more information.