In the following English vocabulary question, you are given a descriptive phrase. Choose, from the four alternatives, the one word that best substitutes the phrase "systematic study and analysis of election trends and voting behaviour".

Introduction / Context:
This one word substitution item asks for the name of a specialised field of study. The phrase given is systematic study of election trends, which clearly points to a discipline that analyses voting patterns, election results and political behaviour of voters.

Given Data / Assumptions:

• The phrase describes systematic study and analysis of election trends and voting behaviour.
• Option A: Archaeology.
• Option B: Psephology.
• Option C: Entomology.
• Option D: Eschatology.
• We assume one of these is the recognised name for the academic field that studies elections.

Concept / Approach:
The correct term is psephology. It comes from a Greek root related to pebbles that were used in ancient voting and now refers to the statistical study of elections and voting. Archaeology is the study of human history through material remains, entomology is the study of insects, and eschatology is the study of last things or end times in religion. None of these other options is connected to elections.

Step-by-Step Solution:
Step 1: Identify the domain: elections, voting trends and voter behaviour.Step 2: Recall that specialists who predict election outcomes by analysing opinion polls and past data are often called psephologists.Step 3: Match this with option B, psephology, the field devoted to such analysis.Step 4: Examine archaeology, which deals with fossils, artefacts and ancient sites, not modern elections.Step 5: Eliminate entomology and eschatology, which relate to insects and theological end times respectively. Therefore, psephology is the only correct substitute.

Verification / Alternative check:
Look at examples from media reports: Psephology has become an important tool for understanding voter preferences before elections. The phrase election psephology is sometimes used when discussing pre poll surveys and exit polls. Using archaeology, entomology or eschatology in this context would confuse the reader and clearly be wrong. This supports the choice of psephology as the correct answer.

Why Other Options Are Wrong:
Archaeology focuses on the physical remains of past human societies, such as pottery, tools and ruins, and does not involve the study of contemporary voting patterns. Entomology is a branch of zoology dealing with insects, for example studying bees or butterflies. Eschatology is a theological discipline that deals with beliefs about judgement, heaven, hell and the end of the world. None of these fields intersect with systematic analysis of election results and voter behaviour.

Common Pitfalls:
Because psephology is an uncommon word in everyday conversation, many candidates may not recognise it immediately. However, it often appears in exam oriented reading passages and in election season news coverage. A practical tip is to connect psephology with polls and predictions. Remembering that psephologists are the experts who appear on television explaining swing percentages will help fix the word in your memory.

Final Answer:
The correct one word substitute for systematic study of election trends is Psephology, so option B is correct.