Selenium TestNG - java.lang.NullPointerException

I've been trying to do a testng test in selenium, but it's throwing the following exception to me when executing:

FAILED: Login
java.lang.NullPointerException
at Vejez.prueba1Vejez.Login(prueba1Vejez.java:30)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.testng.internal.MethodInvocationHelper.invokeMethod(MethodInvocationHelper.java:124)
at org.testng.internal.Invoker.invokeMethod(Invoker.java:580)
at org.testng.internal.Invoker.invokeTestMethod(Invoker.java:716)
at org.testng.internal.Invoker.invokeTestMethods(Invoker.java:988)
at org.testng.internal.TestMethodWorker.invokeTestMethods(TestMethodWorker.java:125)
at org.testng.internal.TestMethodWorker.run(TestMethodWorker.java:109)
at org.testng.TestRunner.privateRun(TestRunner.java:648)
at org.testng.TestRunner.run(TestRunner.java:505)
at org.testng.SuiteRunner.runTest(SuiteRunner.java:455)
at org.testng.SuiteRunner.runSequentially(SuiteRunner.java:450)
at org.testng.SuiteRunner.privateRun(SuiteRunner.java:415)
at org.testng.SuiteRunner.run(SuiteRunner.java:364)
at org.testng.SuiteRunnerWorker.runSuite(SuiteRunnerWorker.java:52)
at org.testng.SuiteRunnerWorker.run(SuiteRunnerWorker.java:84)
at org.testng.TestNG.runSuitesSequentially(TestNG.java:1208)
at org.testng.TestNG.runSuitesLocally(TestNG.java:1137)
at org.testng.TestNG.runSuites(TestNG.java:1049)
at org.testng.TestNG.run(TestNG.java:1017)
at org.testng.remote.AbstractRemoteTestNG.run(AbstractRemoteTestNG.java:114)
at org.testng.remote.RemoteTestNG.initAndRun(RemoteTestNG.java:251)
at org.testng.remote.RemoteTestNG.main(RemoteTestNG.java:77)

my code is as follows:

package Vejez;

import org.openqa.selenium.By;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.chrome.ChromeDriver;
import org.openqa.selenium.chrome.ChromeOptions;
import org.testng.annotations.AfterTest;
import org.testng.annotations.BeforeTest;
import org.testng.annotations.Test;

public class prueba1Vejez {

public String baseUrl = "https://accounts.google.com/";
String driverPath = "C:\chromedriver.exe";
public WebDriver driver ;

@BeforeTest
public void launchBroser() {
    System.out.println("launching chrome browser"); 
    System.setProperty("webdriver.chrome.driver", driverPath);
    ChromeOptions options = new ChromeOptions();
    options.addArguments("start-maximized");            
    WebDriver driver = new ChromeDriver(options);
    driver.get(baseUrl);

}

@Test (priority = 0)
public void Login() {
    driver.findElement(By.id("identifierId")).sendKeys("[email protected]");
}

/*
@AfterTest
public void CloseExplorer() {
    driver.close();
} */



}

would someone have an idea of what the error might be? first of all, Thanks.