Answer:
A. Multifactor authentication
Explanation:
Multifactor authentication is a security system process that requires a user to verify his or her identity by providing two categories of credentials.
A mobile device user has entered her user ID and password to access an online account, she immediately receives a text message with a unique PIN or One Time Password (OTP) that must be entered before she is granted access to the account. This is an example of a multifactor authentication security method.
Answer:
No you can not tell that recursion is ever required to solve a problem.
Recursion is required when in the problem, the solution of the input depends on the solution of the subsets of the input.
Iteration is also another form of repetitive approach we follow to solve that kind of problems.
But the difference between recursion and iteration is :
- In recursion we call the function repeatedly to return the result to next level.
- In iteration certain bunch of instructions in a loop are executed until certain conditions met.
Explanation:
For example in the Fibonacci sequence problem, to find
, we need to compute
and
before that.
- In case of recursion we just call the method Fibonacci(n) repeatedly only changing the parameter Fibonacci(n-1), that calculates the value and return it.
Fibonacci(n)
1. if(n==0 or n==1)
2. return 1.
3.else
4. return( Fibonacci(n-1)+Fibonacci(n-1) )
- But in case of iteration we run a loop for i=2 to n, within which we add the value of current
and
to find the value of 
Fibonacci(n)
1. if(n<=2)
2. result = 1
3. else
4. result1 =1 and result2=1.
5. { result = result1 +result2.
6. result1= result2.
7. result2 = result.
8. }
9. output result.
Answer:First of all, to work safely at the internet you should avoid any not secure page, and if you can’t do that, avoid entering stuff such as credit cards or passwords on this sites. Now, to work safely it’s recomendable to have a VPN(virtual private network), that hides your IP direction.
Explanation:
Lights of New York was the 1928 what film was the first all talking feature.