Strontium hydroxide solution reacts with perchloric acid in a neutralization reaction. A 25.0 mL sample of an HClO₄ solution was neutralized by 29.0 mL of a 0.105 M Sr(OH)₂ solution. Find the concentration (mol/L) of the perchloric acid solution. 
Sr(OH)₂(aq) + 2 HClO₄(aq) → 2 H₂O(l) + Sr(ClO₄)₂(aq)

• A. 0.105 M
• B. 0.210 M
• C. 0.244 M
• D. 0.262 M

Answer: (C)