Step 1: Know when World Homeopathy Day is observed.
World Homeopathy Day (WHD) is observed every year on April 10 to honour Dr. Samuel Hahnemann, the founder of Homeopathy, on his birth anniversary.
Step 2: Recall the 2026 theme.
The theme for World Homeopathy Day 2026 was "Homeopathy for Holistic Health," emphasizing the comprehensive mind-body-spirit approach that homeopathic medicine promotes.
Step 3: Eliminate the other options.
"Sustainable Health," "Community Wellness," and "Universal Health" sound plausible but are not the official 2026 theme. The keyword to remember is "Holistic Health."
\[ \boxed{\text{Homeopathy for Holistic Health}} \]