What popular music genre of the 1950s and 1960s combines gospel music with elements of rhythm and blues?

The correct answer is soul music. This genre emerged in the United States during the late 1950s and became especially prominent in the 1960s. Soul music is characterized by its distinctive blend of elements from gospel music and rhythm and blues, incorporating passionate vocals and strong emotional resonance that reflect the spiritual and cultural experiences of African American communities.

Soul music's roots in gospel are evident through its use of call-and-response patterns, powerful vocal delivery, and themes of love, pain, and hope. Artists such as Aretha Franklin, Otis Redding, and Marvin Gaye are iconic figures of this genre, whose music epitomizes the soulful expression that defines the era.

The other genres mentioned, while also significant in their own right, do not encapsulate this specific combination of influences in the same way. Blues primarily focuses on themes of hardship and emotion in a different musical structure. Axe and kwassa kwassa are genres related to African music and dance styles, which do not relate directly to the fusion of gospel and rhythm and blues that characterizes soul music.