Consider a variable var with some value in it. How can we achieve an output of this format:

To achieve the desired output format, you should use string formatting to include the value of the variable in the output string. Here's how you can do it in Python:

```python
var = "your_value" # Replace `your_value` with the actual value you want
print(f"This is the value of variable one: {var}")
```

This uses an f-string (formatted string literal), which is a modern and convenient way to format strings in Python.

If you are choosing from the options you provided, the second option would be the most applicable, but it should be correctly done as follows:

```python
print('This is the value of variable one:', var)
```

Please note that the first response in your options appears to be incorrectly formatted (it doesn’t use quotes around the format string). The correct way is to either use f-strings or the comma syntax as shown.