select 
c.prefijo,
c.abonado,
e.descr,
a.numdeco,
b.DESCMODECO, 
b.FECALTA,
c.finst

from 
NSRDC as A,
modeco as B,
gigaredcierre.dbo.ae201808 as C,
servicio as E

where a.CODMODECO = b.CODMODECO 
and c.numdeco = a.numdeco
and c.datcodserv=e.datcodserv
and  b.datcodserv=e.datcodserv

order by c.abonado asc