Отметь формулу \(2\)-аминобутановой кислоты.

• (\begin{equation*}
  \begin{array}{l}
  \underset{|}{\mathrm{C}}H_{2}-CH_{2}-CH_{2}-COOH \
  NH_{2}
  \end{array}
  \end{equation*})
• (\begin{equation*}
  \begin{aligned}
  CH_3-CH_2-\underset{|}{C}H-COOH \
  ,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,\ NH_2
  \end{aligned}
  \end{equation*})
• \(\begin{aligned} &\underset{|}{\mathrm{C}} \mathrm{H}_{2}-\underset{|}{\mathrm{C}} \mathrm{H}-\mathrm{COO}-\mathrm{CH}_{3} \\ &\mathrm{CH}_{3} \quad \quad \quad \quad \quad \quad \mathrm{NH}_{2} \end{aligned}\)
• (\begin{equation*}
  \begin{array}{l}
  CH_3-\underset{|}{C}H-CH_2-COOH \
  ,,,,,,,,,,,,,,,,,,,,,,NH_2
  \end{array}
  \end{equation*})