Here's why:

* Lipids are a broad category of molecules that are generally hydrophobic (water-repelling). They include fats, oils, waxes, and steroids.

* Steroids are a specific type of lipid that have a characteristic four-ring structure. They are involved in a wide variety of biological processes, including hormone production, cell signaling, and membrane structure.

Let's look at why the other options are incorrect:

* Proteins are made up of amino acids.

* Carbohydrates are made up of sugars.

* Nucleic acids (like DNA and RNA) are made up of nucleotides.