Let \[{{v}_{1}}\] be the frequency of series limit of Lyman series, \[{{v}_{2}}\] the frequency of the first line of Lyman series and \[{{v}_{3}}\] the frequency of series limit of Balmer series. Then which of the following is correct?

• A. \[{{v}_{1}}-{{v}_{2}}={{v}_{3}}\]    
• B. \[{{v}_{2}}-{{v}_{1}}={{v}_{3}}\]
• C. \[{{v}_{3}}=\frac{1}{2}({{v}_{1}}+{{v}_{2}})\]
• D. \[{{v}_{2}}+{{v}_{1}}={{v}_{3}}\]