If we took A as a starting ,then we can take C or D,for each we can make 6 sequences(let A,C, then (B,D,E) in 3! Way..)so total 12 seq...
If we took C as start,then we can arrange A,B,D,E in 4! Way
And same for if we start by taking D,then we can also get 4! Seq..
Total = 24+24+12 =60 sequences