Considering the algorithms for page replacement, w hich of the following is true?$($a$)$ the second chance algorithm uses an ordered pair $($ used, modified$)$ to select thevictim $($b$)$ the additional$-$reference$-$bits algorithm gains additional orderinginformation by recording the reference bits at regular intervals $($c$)$ LRU algorithm isoptimal $($d$)$ Beladys algorithm suffers from Beladys anomaly