plz solve 16 to 19

1S, BNF grammars do not allow left-recunsive rules Multiple choice, choase the best answer from the given options 16. Java solves the Dangling ELSE Problem by a. Using simple syntax and an ambiguous grammar but have an extemal nale to broak the ambiguit b. Uses a complex but an unumbiguous grammar to avoid the Dangling ELSE problem c. Avoiding the ambiguity by having a more complex syntax (c.g. has a built-in end marker such a'ndit d. Requiring braces (parenthesizing) when an "else" follows am "if e. Requiring every "if to be paired with an "else" 17, C solves the Dangling ELSE Problem by syntax and an ambiguous grammar but have an external rule to break the ambiguity a. Using simple b. Uses a complex but an unambiguous grammar to avoid the Dangling ELSE problem c. Avoiding the ambiguity by baving a more complex syntax (e.g. has a built-in end marker such as endif) d. Requiring braces (parenthesizing) when an "else" follows an "if e. Requiring every "if" to be paired with an "else". 18. Ada solves the Dangling ELSE Problem by a. Using simple syntax and an ambiguous grammar but have an extemal rule to break the ambiguaity b. Uses a complex but an unambiguous grammar to avoid the Dangling ELSE problem. c. Avoiding the ambiguity by having a more complex syntax eg. has a built-in end marker such d. Requiring braces (parenthesizing) when an else" follows an "if e. Requiring every "if" to be paired with an "else" in Matching 19. tomim" Consider formal languages and a given alphabet of a,b,c,d, match each ofthe following regular ex representation (A-H). For each regular expression (a-e) has one representation (A-H) no repeats a. (alb)* b. (alb)+ c. (ab)|(cd) d. ((ab)l(cd))*c A. 0 B.{ } C. (ab,cd) D. (a,b,aa,ab,ba,bo.... F. {ac, be, aac, bac bbc G. (e, abe, ede, abede, cdedc, odabe, abab 1 H. none of the above e. Spring 2018