1. Arduino GPIO Basics

Lisa uses the following code. She is observing the Serial Monitor. What will be printed on the Serial Monitor if the button is not pressed?

const int buttonPin = 2;
int buttonState = 0;

void setup() {
  	pinMode(buttonPin, INPUT_PULLUP);
	Serial.begin(9600);
}

void loop() {
  	buttonState = digitalRead(buttonPin);
	Serial.println(buttonState);
}