Pick all that apply

• 1Choice 1.

  It evicts the item with the fewest accesses first, so hot data used over and over doesn't get pushed out by a scan that passes through once

• 2Choice 2.

  Plain LFU has the problem that items popular in the past stay long after they stop being used, so a time decay (aging) is sometimes added

• 3Choice 3.

  An O(1) LFU is built from doubly linked lists per frequency tied together by a hash map, and the oldest node in the minimum frequency list is the eviction target

• 4Choice 4.

  LFU always has a higher hit rate than LRU, so it should be the default choice for a mobile cache

• 5Choice 5.

  Frequency counters have to be sorted, so an O(log n) heap is required and an O(1) implementation is impossible