Final answer:
Tech A is correct; ammeters must be connected in series within a circuit to measure amperage accurately. Tech B's method does not create a series circuit and thus is incorrect.
Step-by-step explanation:
Tech A is correct in saying that to read amperage, an ammeter must be connected in series with the circuit component whose current is to be measured. This series connection is necessary because all components in series have the same current flowing through them. It essentially means that the ammeter will become part of the circuit, so it can measure the current passing directly through it.
Tech B's method is incorrect because placing one lead of the ammeter on the input side and the other on the output side of the load without forming a series circuit fails to ensure that all the current flows through the ammeter. Instead, the ammeter should be connected in such a way that the current enters the 'input' terminal of the ammeter and exits through the 'output' terminal, thus ensuring the device is in series with the component in question.
When measuring current, care should be taken to ensure that the ammeter's resistance is negligible compared to the rest of the circuit to avoid significantly affecting the current being measured.