Diode Schematic Symbol

Look at the four Schematic Symbols shown in Figure A-1. Each of the symbols is labeled with a number…?
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5. Look at the four schematic symbols shown in Figure A-1. Each of the symbols is labeled with a number. Which of the following statements about these symbols is correct?
A. Symbol 1 represents a diode, symbol 2 represents a resistor, symbol 3 represents an LED, and symbol 4 represents a transistor.
B. Symbol 1 represents a diode, symbol 2 represents an LED, symbol 3 represents a transistor, and symbol 4 represents a resistor.
C. Symbol 1 represents a transistor, symbol 2 represents a resistor, symbol 3 represents an LED, and symbol 4 represents a diode.
D. Symbol 1 represents a transistor, symbol 2 represents a diode, symbol 3 represents a resistor, and symbol 4 represents an LED.
Answer is
D. Symbol 1 represents a transistor, symbol 2 represents a diode, symbol 3 represents a resistor, and symbol 4 represents an LED.
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