Which among the following is not the correct symbol?

• A. Size- l
• B. Velocity ‚Äö√Ñ√∂‚àö√ë‚àö¬® v
• C. Gravity ‚Äö√Ñ√∂‚àö√ë‚àö¬® g
• D. Viscosity ‚Äö√Ñ√∂‚àö√ë‚àö¬® a