Statins are pharmacological agents, but their efficacy can be significantly improved when combined with lifestyle changes. Regular physical activity, such as brisk walking or aerobic exercise, improves cardiovascular health and helps raise HDL ("good") cholesterol. A fiber-rich diet binds cholesterol in the digestive tract and reduces its absorption, thereby lowering LDL levels.
Option (a) A high-fat diet can worsen cholesterol levels.
Option (b) Sedentary behavior is associated with cardiovascular risk.
Option (d) Smoking damages blood vessels and increases the risk of heart disease.
Hence, the best complementary option is (c).