Ace the NANP Board Exam 2025 – Unleash Your Natural Health Mojo!

Unsaturated fatty acids are known for having double bonds between their carbon atoms. These bonds are what characterize unsaturated fatty acids and make them different from saturated fatty acids. Option A, carboxyl groups, are present in both saturated and unsaturated fatty acids, so this cannot be the correct answer. Option C, methyl groups, are also present in both types of fatty acids, so this is not the correct answer either. Option D, no double bonds between carbon atoms, is in fact the opposite of what characterizes unsaturated fatty acids, making it an incorrect answer. Therefore, the correct answer is B, double bonds between carbon atoms.