is just a simple fraction addition, let's first convert the mixed fractions to improper, and then add them up.
[tex] \bf \stackrel{mixed}{1\frac{5}{8}}\implies \cfrac{1\cdot 8+5}{8}\implies \stackrel{improper}{\cfrac{13}{8}}
\\\\\\
\stackrel{mixed}{2\frac{1}{3}}\implies \cfrac{2\cdot 3+1}{3}\implies \stackrel{improper}{\cfrac{7}{3}}
\\\\[-0.35em]
~\dotfill\\\\
\cfrac{13}{8}+\cfrac{7}{3}\implies \stackrel{\textit{using an LCD of 24}}{\cfrac{(3)13+(8)7}{24}}\implies \cfrac{39+56}{24}\implies \cfrac{95}{24}\implies 3\frac{23}{24} [/tex]
now, which of those models, does not add up to 95/24?
[tex] \bf 1+2+\cfrac{6}{11}\implies \cfrac{1}{1}+\cfrac{2}{1}+\cfrac{6}{11}\implies \stackrel{\textit{using an LCD of 11}}{\cfrac{(11)1+(11)2+(1)6}{11}}
\\\\\\
\cfrac{11+22+6}{11}
\implies
\cfrac{39}{11}~~\bigotimes [/tex]
you can check the others, and notice that they sum up to 95/24.
