$(b(b(b|)|)|)$

A$)$ All strings over $$ that start with $a$ or $b$ and have a multiple three of $e^{2}s.$

C$)$ All strings over $$ that start with $a$ or $b$ and have an even nurmber of $e^{\text{'}}$ s

D$)$ All strings over $$ that start with $a$ or $b$ and have at least three $e\text{'}$s$.$

E$)$ None of the above.

All strings over $\{a,b,c\}$ containing two or more $a^{}$ s$.$

A$)(c(c(c|)|)|)$

B$){}^{**}{a}^{+}{}^{**}{a}^{+}{}^{**}$

C$){}^{**}a{}^{**}a{}^{**}$

D$)(c(c|)|)$

E$)$ None of the above.

All strings of digits in which $2\text{'}$s and $3\text{'}$s never occur after $8\text{'}$s and $9\text{'}$s $?$

A$)(7(9|)|)$

B$)(7(9|)|)$

C$)(3(9|)|)$

D$)(9(7|)|)$

E$)$ None of the above.

All strings over $$ in which there is no substring $aa.$

A$)(b((c(c|)|))|)$

B$)(c((c(lon|)|))|)$

C$)(c(c(c|)|)|)$

D$)a^{**}(b|c|lon)a^{**}(b|c|lon)a^{**}(b|c|lon)a^{**}$

E$)$ None of the above.