Concept:Subsidiary books are special journals used to record and group transactions of a similar nature.
Explanation:Each subsidiary book is meant for one specific kind of transaction to keep accounting organised.
For example, the sales book records all credit sales, while the purchases book records all credit purchases.
The cash book records cash receipts and payments.
These books are not made for transactions of the same period or minor amounts.
They also require source documents before any entry is made.
Grouping similar transactions reduces the number of entries in the main ledger and makes the work easier to manage.
Therefore, the purpose of subsidiary books is to record transactions that are alike in nature.
Answer:B. of a similar nature