Which of the following reflects an inflation rate component?

The change in consumer prices over time is indicative of the inflation rate component because inflation is fundamentally about the rate at which the general level of prices for goods and services is rising. This specific measurement captures how much more expensive a set of goods and services has become over a certain period, thus directly reflecting purchasing power and the economic environment.

In contrast, the interest applied to investments relates more to returns on those investments and can be influenced by various factors, including the prevailing inflation rate, but does not represent the inflation rate itself. Fluctuations in foreign exchange rates pertain to currency value changes between different countries and reflect economic dynamics and trading conditions rather than direct price increases of goods and services. Lastly, the yields of government securities can indicate investor expectations about inflation but again do not directly measure the inflation rate. They are often influenced by inflation but serve as a separate financial indicator. Hence, the change in consumer prices over time is the most direct reflection of inflation.