Arrange the given words in the sequence in which they occur in a standard English dictionary: 1. Effacers 2. Effacing 3. Effaceable 4. Effacements 5. Effacement.

Introduction / Context:
This dictionary order problem features several related words built from the root Efface. Candidates must place Effacers, Effacing, Effaceable, Effacements and Effacement in the sequence in which they appear in a dictionary. Because these words share a long common prefix, the decision depends on understanding the detailed lexical comparison rules and the behavior of words that differ only in suffixes.

Given Data / Assumptions:
- Words: 1. Effacers, 2. Effacing, 3. Effaceable, 4. Effacements, 5. Effacement.
- Standard English dictionary ordering applies.
- Case is ignored; only letters matter.
- If one word is a prefix of another, the shorter one comes first.

Concept / Approach:
Because all words start with Efface or Effac, we first group by this prefix and then examine the remaining letters. We compare letter by letter from left to right. When we reach a position where two words differ, the word with the smaller letter at that position comes first. If one word ends and the other continues, the finished (shorter) word comes first. Applying these rules reveals the correct ordering among the related forms.

Step-by-Step Solution:
Step 1: Identify the full spellings: Effaceable (3), Effacement (5), Effacements (4), Effacers (1), Effacing (2). Step 2: Notice that Effaceable, Effacement and Effacements all begin with Efface. Effacers and Effacing begin with Effac but not Effacea. Step 3: Among Effaceable (Effaceable), Effacement (Effacement) and Effacements (Effacements), after the common Efface, we have a, m, m respectively as the next key letters. Step 4: Since a comes before m, Effaceable (3) comes before Effacement (5) and Effacements (4). Step 5: Compare Effacement (5) and Effacements (4): Effacement is a prefix of Effacements, so Effacement (5) comes before Effacements (4). Step 6: Now consider Effacers (1) and Effacing (2), which are spelled Effacers and Effacing. After Effac, the next letters are e in Effacers and i in Effacing. Step 7: Since e comes before i, Effacers (1) comes before Effacing (2). Step 8: Combine all suborders: the correct dictionary order is Effaceable (3), Effacement (5), Effacements (4), Effacers (1), Effacing (2) or 3, 5, 4, 1, 2.

Verification / Alternative check:
To verify, list the words as Effaceable, Effacement, Effacements, Effacers, Effacing and compare them directly. The Effacea forms sit before the Effacer forms because a comes before r and i. Within Effacement and Effacements, the shorter word Effacement precedes its longer extension Effacements. Then, for the Effacers and Effacing group, the letter e in Effacers precedes i in Effacing. Mapping this confirmatory order back to the question numbers yields 35412, matching the selected option.

Why Other Options Are Wrong:
Option A (34125) places Effacements before Effacement which contradicts the prefix rule. Option C (43152) and option D (43215) both disrupt the internal order among the Effaceable, Effacement and Effacements group and the Effacers, Effacing group. Option E (34512) also misorders the Effacers and Effacing pair. Only option B properly follows lexicographic rules.

Common Pitfalls:
Because the words look very similar, examinees may rely on rough intuition instead of exact comparisons, leading to swaps between Effacement and Effacements or Effacers and Effacing. Another pitfall is ignoring the rule about prefixes where shorter words must come first. To avoid mistakes, carefully write the full words, underline their common parts, and then explicitly compare their differing suffixes.

Final Answer:
The correct dictionary order of the given words is encoded as 35412.