In the following passage there are blanks, each of which has been denoted by a letter. For each blank, five options are given. Choose the most appropriate word from the options that fits the blank appropriately.

India's digital payment ecosystem has undergone a __(A)__ transformation in the last decade. The launch of the Unified Payments Interface (UPI) in 2016 proved to be a __(B)__ moment, enabling instant bank-to-bank transfers through simple mobile applications. Within a few years, UPI transactions __(C)__ into billions every month, far __(D)__ the volume of traditional card-based payments. The government's push for financial inclusion, __(E)__ by the Jan Dhan Yojana and the broad penetration of low-cost smartphones, created a __(F)__ environment for digital wallets and payment apps to __(G)__ in smaller cities and rural areas.

Which of the following fit in the given blank (C)?

The correct option is Surged.

To determine the most appropriate word for blank (C), we need to analyze the context of the sentence:
"Within a few years, UPI transactions __(C)__ into billions every month, far __(D)__ the volume of traditional card-based payments."

The sentence describes a massive growth in the volume of Unified Payments Interface (UPI) transactions over a short period of time, reaching "billions every month" and overtaking traditional card-based payments.

Let us evaluate each of the given options:
1. Surged: This verb means to increase suddenly and powerfully. In the context of transaction volumes rising rapidly to billions, "surged" fits perfectly.
2. Declined: This means to decrease or become less. This directly contradicts the phrase "into billions every month" which indicates rapid growth.
3. Stabilised: This means to become unlikely to change or fail, or to remain at a steady level. This does not capture the dynamic, explosive growth implied by the passage.
4. Collapsed: This means to fall down or fail suddenly. This is the opposite of growing into billions.
5. Trickled: This means to flow or move slowly in small numbers or quantities. This is incorrect because "billions" represents an extremely large, fast-flowing volume rather than a small trickle.

Therefore, Surged is the most suitable word for the blank as it correctly conveys the rapid and massive expansion of UPI transactions.