To render the customLandingPage template given the file structure in the question, the correct ISML method call is:
* D. ISML.renderTemplate('content/custom/customLandingPage');This method correctly specifies the path to the template relative to the cartridge path. The renderTemplate function is used to render an ISML template, and the provided path should accurately reflect the template's location within the file structure, ensuring that the right content is rendered.
This approach is consistent with best practices for organizing and referencing ISML templates in Salesforce B2C Commerce, ensuring accurate rendering of the desired content.