Muriatic acid is a weak solution of:

Muriatic acid is indeed a term commonly used to refer to hydrochloric acid, which is a strong acid. However, it is typically sold as a diluted solution for various applications, making it accessible and safer to handle for specific tasks such as cleaning and pH adjustment in swimming pools.

Hydrochloric acid is a clear, colorless solution of hydrogen chloride gas in water, and while it is classified as a strong acid, the term "muriatic acid" specifically refers to the concentrated form or less pure version that is sold for various uses. This can be somewhat misleading as the term implies a weaker solution, but in practice, it is still a strong acid.

This choice reinforces the understanding that muriatic acid is essentially still a form of hydrochloric acid but is often used in a diluted state for practical purposes. The other acids mentioned are different compounds entirely and do not relate to the common usage or characteristics of muriatic acid.