35 I think E is the best answer.
Until recently, zoologists believed that
all species of phocids (true seals), a pin-
niped family, use a different maternal
strategy than do otariids (fur seals and
sea lions), another pinniped family. Mother
otariids use a foraging strategy. They
acquire moderate energy stores in the
form of blubber before arriving at breeding
sites and then fast for 5 to 11 days after
birth. Throughout the rest of the lactation
(milk production) period, which lasts from
4 months to 3 years depending on the
species, mother otariids alternately for-
age at sea, where they replenish their fat
stores, and nurse their young at breed-
ing sites. Zoologists had assumed that
females of all phocid species, by contrast,
use a fasting strategy in which mother
phocids, having accumulated large energy
stores before they arrive at breeding sites,
fast throughout the entire lactation period,
which lasts from 4 to 50 days depending on
the species. However, recent studies on
harbor seals, a phocid species, found that
lactating females commenced foraging
approximately 6 days after giving birth and
on average made 7 foraging trips during
the remainder of their 24-day lactation period.
According to the passage, until recently zoologists believed which of the following about all phocid mothers?
A. Their fasting periods after giving birth were typically shorter than those of otariids.
( the passage only talks about one kind of phocid species with the fast period, so it can not compare "Their fasting periods" with "those of otariids")
E.They replenished their fat stores only after their lactation period ended.
( see the highlights with blue)
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